The goals of this program are to contribute to a basic understanding of the pathophysiology of thrombosis and hemostasis, particularly as it relates to two interacting proteins, fibrinogen and fibronectin (CIg). Specific areas of investigation include: structure of adult and fetal fibrinogen; structure of fibrinogen variants and of congenital dysfibrinogenemias; packing arrangement of fibrin molecules comprising a fibrin clot; structure and function of plasma fibronectin and elucidation of the nature of its interactions with heparin, fibrin(ogen) and other molecules; the mechanism of fibrinogen biosynthesis, assembly, and secretion; clinical investigation of plasma and tissue fibronectin in certain disease states. A variety of biochemical, immunochemical, biophysical, electron microscopic, spectroscopic, and tissue culture techniques are to be applied in various combinations for achieving our research objectives.